A few days ago my laptop was working perfectly - was able to play a game, watch a movie, boot into all of the OSes I have installed; flawless. Yesterday, after work, I attempted to boot up my laptop to find that the LED on the power button would turn on for a few seconds and then shut off. No beep, no post, nothing. I attempted to boot up in various ways - with battery only, with AC adapter only, with both - no luck, I would get the same result each time. I figured the processor might be overheating or the RAM became a little loose so I opened my laptop up, reseated the RAM, reseated the CPU, applied new thermal paste (Arctic Silver!), put the heatsink & fan back on, and reseated the hard drive. Still, the same result - the laptop wouldn't POST. I kept my laptop open and watched as I turned it on - no fans would spin, but the LED would turn on, then turn off after a few seconds. I tested the AC adapter with my multimeter and it seems to be functioning properly, so I am starting to presume something is wrong with the power converter on the motherboard. If anyone has any suggestions or insight into this, please let me know. Thanks for your help! "Everything begins with Nu and everything ends with Nu. This is the truth! This is my belief... at least for now." - Mysteries of Life Volume 184 Chapter 26

You could try disconnecting the hard drive and any other devices. You can even try pulling the RAM. If the motherboard is working tou should get the POST beep without anything else connected, or at least error beeps. Error beeps indicate the motherboard/CPU is working to some extent.

I removed my RAM and Hard Drive (left in the bluetooth adapter, though). I attempted to boot the system again and the same thing happens - LED turns on for a few seconds then shuts off. No beeps and no POST. I do remember, though, that when the computer WAS working correctly, there never was a beep when it did POST, if that helps. "Everything begins with Nu and everything ends with Nu. This is the truth! This is my belief... at least for now." - Mysteries of Life Volume 184 Chapter 26

I've also noticed that with the AC adapter plugged in, if I attempt to power the machine on (with it resulting in shutting off), I am unable to attempt it again until I remove the AC adapter and plug it back in. At this rate, I figure I might have to warranty the machine, as annoying as it may be. "Everything begins with Nu and everything ends with Nu. This is the truth! This is my belief... at least for now." - Mysteries of Life Volume 184 Chapter 26

If it's under Warranty, you have nothing to loose, except your Warranty, if you undertake too much. There is nothing to learn from someone who already agrees with you.